/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

/*
 * libc.c
 *
 * This file contains our wrappers/reimplementations for "standard"
 * libc functions.  Things like "memcpy."  We add to this as we need
 * it.  Oh, and let's keep it in alphabetical order, should it ever
 * get large.  Most string/character stuff should be in utf8.c, not
 * here.  This file (and maybe utf8.c) should be the only ones in
 * NSS to include files with angle brackets.
 */

#ifndef BASE_H
#include "base.h"
#endif /* BASE_H */

#include <string.h> /* memcpy, memset */

/*
 * nsslibc_memcpy
 * nsslibc_memset
 * nsslibc_offsetof
 * nsslibc_memequal
 */

/*
 * nsslibc_memcpy
 *
 * Errors:
 *  NSS_ERROR_INVALID_POINTER
 *
 * Return value:
 *  NULL on error
 *  The destination pointer on success
 */

NSS_IMPLEMENT void *
nsslibc_memcpy(void *dest, const void *source, PRUint32 n)
{
#ifdef NSSDEBUG
    if (((void *)NULL == dest) || ((const void *)NULL == source)) {
        nss_SetError(NSS_ERROR_INVALID_POINTER);
        return (void *)NULL;
    }
#endif /* NSSDEBUG */

    return memcpy(dest, source, (size_t)n);
}

/*
 * nsslibc_memset
 *
 * Errors:
 *  NSS_ERROR_INVALID_POINTER
 *
 * Return value:
 *  NULL on error
 *  The destination pointer on success
 */

NSS_IMPLEMENT void *
nsslibc_memset(void *dest, PRUint8 byte, PRUint32 n)
{
#ifdef NSSDEBUG
    if (((void *)NULL == dest)) {
        nss_SetError(NSS_ERROR_INVALID_POINTER);
        return (void *)NULL;
    }
#endif /* NSSDEBUG */

    return memset(dest, (int)byte, (size_t)n);
}

/*
 * nsslibc_memequal
 *
 * Errors:
 *  NSS_ERROR_INVALID_POINTER
 *
 * Return value:
 *  PR_TRUE if they match
 *  PR_FALSE if they don't
 *  PR_FALSE upon error
 */

NSS_IMPLEMENT PRBool
nsslibc_memequal(const void *a, const void *b, PRUint32 len,
                 PRStatus *statusOpt)
{
#ifdef NSSDEBUG
    if ((((void *)NULL == a) || ((void *)NULL == b))) {
        nss_SetError(NSS_ERROR_INVALID_POINTER);
        if ((PRStatus *)NULL != statusOpt) {
            *statusOpt = PR_FAILURE;
        }
        return PR_FALSE;
    }
#endif /* NSSDEBUG */

    if ((PRStatus *)NULL != statusOpt) {
        *statusOpt = PR_SUCCESS;
    }

    if (0 == memcmp(a, b, len)) {
        return PR_TRUE;
    } else {
        return PR_FALSE;
    }
}

/*
 * nsslibc_memcmp
 */

NSS_IMPLEMENT PRInt32
nsslibc_memcmp(const void *a, const void *b, PRUint32 len, PRStatus *statusOpt)
{
    int v;

#ifdef NSSDEBUG
    if ((((void *)NULL == a) || ((void *)NULL == b))) {
        nss_SetError(NSS_ERROR_INVALID_POINTER);
        if ((PRStatus *)NULL != statusOpt) {
            *statusOpt = PR_FAILURE;
        }
        return -2;
    }
#endif /* NSSDEBUG */

    if ((PRStatus *)NULL != statusOpt) {
        *statusOpt = PR_SUCCESS;
    }

    v = memcmp(a, b, len);
    return (PRInt32)v;
}

/*
 * offsetof is a preprocessor definition
 */